With the continuous development of broadband active phased array radars, the demand for antenna beam control has been increasing, and the research on control circuit has been deepened.
As a key device for beam control, a phase shifter is always one of the key devices in an antenna transceiver module because of its many working states and technical features, large area occupation, high performance requirements, and high difficulty in design and manufacture. The development of the phased array radar has raised higher requirements on the bandwidth, phase-shifting accuracy and integrated area of the phase shifter, and other aspects. Therefore, it has great significance and practical value in researching broadband and ultra wide band high-performance phase shifters.
A reflective phase shifter is widely used in designing wideband phase shifters, wherein a traditional 3 dB coupler such as Lange coupler is larger in area, which is not beneficial for integration, and also increases the circuit cost. It is very difficult for a traditional reflective circuit to meet the band requirements of ultra wide band.
Therefore, it is very necessary to develop a compact ultra wide band digital phase shifter which can widen the bandwidth and reduce the circuit area.